Heat exchanger



Dec. 22, 1942. c. A.'QUILLEN HEAT EXCHANGER Fi led Nov. 15, 1940 4[NWT/V709, CLARENCE A. -Qu/zz/v,

.JTTO/P/YEVS.

Patented Dec. 22, 1942 UNITED s rew orica HEAT EXCHANGER Clarence A.Quillen, Indianapolis, Ind.

Application November 15, 1940, Serial No. 365,751

1 Claim.

This invention relates to a heat exchanger of the tubular type, and itis a primary object to form permanent joints or seals at each end or" ametal tube into which other tubes are carried, all without having toemploy separate castings or fittings for the purpose.

An important advantage of the invention is found in the fact that notonly is there a great saving in cost of material by elimination offittings but also there is a considerable reduction in the labor cost ofassembling and forming the seals. A further very important advantage isthat a seal is formed at once in such a manner that there is no dangerof melting or destroying other parts of a seal as has heretofore beenthe case when a fitting was employed requiring the brazing or sweatingin one part in one step and a subsequent like operation in a second stepwherein the heat required was likely to open up the seal formed in thefirst instance.

These and other objects and advantages of the invention will becomeapparent to those versed in the art in the following description of oneparticular form of the invention as illustrated in the accompanyingdrawing, in which Fig. 1 is a side view in partial section of astructure embodying the invention;

Fig. 2, a view in transverse section on the line 22 in Fig. 1;

Fig. 3, a view in transverse section on the line Fig. 5, a side view ofan elementary form of die for forming the end of the exchanger tube;

and

Fig. 6, a view in end elevation of the die.

Like characters of reference indicate like parts throughout the severalviews in the drawing.

Referring to the drawing, a tube It! adapted to carry a refrigerantfluid is carried entirely through a length of tubing II of largerdiameter so that the tube I I] will extend by both ends from therespective ends of the tube II. Then in one end of the tube II isinserted a smaller diameter tube I2 by a short length thereof only andin the same manner the end of a small diameter tube I3 is inserted intothe opposite end of the tube I I for a short distance only.

Each end of the tube II is then deformed by any means, such as by thetwo-part die, as illustrated in Figs. 5 and 6, to press the tube Itcircumferentially around the tube 50 and thence around that part of thetube I2 inserted there within, causing the wall of the tube II then toassume that shape as shown in cross section in Fig. 2. The die, as aboveindicated, is formed in the twoparts It and i5. A hole I5 is formedtherethrough and centered on the dividing line between the two diesections and a second hole I? of smaller diameter is likewise formedtherethrough and centered on the same parting line. The circumferencesof the two holes intersect to leave an opening therebetween. Theshoulders left on either side of this opening I8 draw the wall of thetubing it around in between the tube It! and the tubes I2 and I3 whenthe die is placed by its two parts around the respective ends of thetube It and forced together with the openings It and H. centering on theaxes of the tube In and the tubes I2, I'3.

Following the deformation of each end of the tube II, the tubes IE1 and52 on the one end and H3 and it; on the other end are then sealed one tothe other by any suitable means, such as by causing metal I9 to flowwithin the tube II and around the tubes II) and I2 and I3 by anysuitable means, such as by soldering and sweating or by brazing. Tofacilitate the entrance of this metal, each end of the tube I I ispreferably flared outwardly into bell-shaped ends, as indicated in Fig.1.

Thus it is to be noted that the seal around the tube Ill and the tube I2is formed in one heating operation as is likewise the seal formed aroundthe tube It] and the tube I3 at the outer end of the tube II. These endsof the tube I i are removed one from the other at quite a distance sothat the seal of one end does not affect the seal previously formed inthe other end. The inwardly extending ribs 20 and ZI'formed by the diein the wall of the tube I I at each end thereof serve to mechanicallyspace the tubes I2 and I3 from the tube I0 and also to limit the amountof metal required to form the seal. The spacing between the tube Iii andthe tubes I2 and I3 within the ends of the tube II is somewhatexaggerated in the drawing in order to show clearly that there is ametal seal introduced between those members to effect a permanent bondtherebetween and therearound.

In the heat exchanger thus formed, the medium being circulated for theabsorption of or dissipation of heat is carried through the tube Ii].Then the device for supplying heat to or removing heat from that mediumin the tube II) is introduced through either tube I2 or I3 anddischarged within the tube II to circulate and flow therewithin aroundthe tube Ill and be discharged from the other end of the tube I Ithrough the other smaller diameter tube I3 or I2 as the case may be,depending upon the direction of flow. This is accomplished all withoutthe use of the heretofore required fittings that were separately sweatedfirst to the tube I0 and then to the tube l2 and finally to the tube II.

Preferably the combined external diameters of the tube I0 and the tubel2 (the tube l3 being of the same external diameter as that of the tubeI2) is made to approximate the internal diameter of the tube II, beingjust sufliciently less to permit the easy insertion within the tube IIof the tube I0 and the tubes I2 and I3 along thereaside. Then when theends of the tube II are deformed, the major external dimension acrossthe deformed end will still remain substantially that of the externaldiameter of the undeformed part of the tube II. The tubes l0,'II, l2 andI3 are made out of suitable metal, such as copper, brass, tin, or thelike as commonly employed in heat exchangers for good heat conductivity.

While I have herein shown and described my invention in the oneparticular form, it is obvious that structural variations may beemployed without departing from the spirit of the invention and I,therefore, do not desire to be limited to that precise form beyond thelimitations as may be imposed by the following claims.

I claim:

In a heat exchanger, a length of major diameter pipe of circularcross-section having an integral end portion shaped in figure 8crosssection defined by the pipe wall being infolded to provide twobores through said portion; a pair of pipes entered into said majordiameter pipe, one through each of said bores, and one pipe continuingthrough the major pipe; and both of said 7 bores having theircross-sectional areas within CLARENCE A. QUILLEN.

